@color:red;
.juzhong(@w:50px,@h:50px,@c:pink){
	position: absolute;
	left: 0;
	right: 0;
	top: 0;
	bottom: 0;
	margin: auto;
	background: @c;
	height: @h;
	width: @w;
}

* {
	margin: 0;
	padding: 0;
}
#wrap {
	position: relative;
	width: 300px;
	height: 400px;
	border: 1px solid;
	margin: 0 auto;
	.inner {
		.juzhong(@c:black);
	}
	.inner2 {
		.juzhong(200px,200px,black);
	}
}
